 /*******************************************************************************
  * Copyright (c) 2000, 2006 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.internal.ide;

 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.jface.dialogs.ErrorDialog;
 import org.eclipse.jface.dialogs.MessageDialog;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Shell;
 import org.eclipse.ui.PartInitException;

 /**
  * Utility class to help with dialogs.
  * <p>
  * Note that a copy of this class exists in the
  * org.eclipse.ui.internal package.
  * </p>
  */
 public class DialogUtil {

     /**
      * Prevent instantiation.
      */
     private DialogUtil() {
     }

     /**
      * Open an error style dialog for PartInitException by
      * including any extra information from the nested
      * CoreException if present.
      */
     public static void openError(Shell parent, String title, String message,
             PartInitException exception) {
         // Check for a nested CoreException
 CoreException nestedException = null;
         IStatus status = exception.getStatus();
         if (status != null && status.getException() instanceof CoreException) {
             nestedException = (CoreException) status.getException();
         }

         if (nestedException != null) {
             // Open an error dialog and include the extra
 // status information from the nested CoreException
 ErrorDialog.openError(parent, title, message, nestedException
                     .getStatus());
         } else {
             // Open a regular error dialog since there is no
 // extra information to display
 MessageDialog.openError(parent, title, message);
         }
     }

     /**
      * Return the number of rows available in the current display using the
      * current font.
      * @param parent The Composite whose Font will be queried.
      * @return int The result of the display size divided by the font size.
      */
     public static int availableRows(Composite parent) {

         int fontHeight = (parent.getFont().getFontData())[0].getHeight();
         int displayHeight = parent.getDisplay().getClientArea().height;

         return displayHeight / fontHeight;
     }

     /**
      * Return whether or not the font in the parent is the size of a regular
      * font. Typically used to know if a font is smaller than the High Contrast
      * Font. This method is used to make layout decisions based on screen space.
      *
      * @param parent The Composite whose Font will be queried.
      * @return boolean. True if there are more than 50 lines of possible
      * text in the display.
      */
     public static boolean inRegularFontMode(Composite parent) {

         return availableRows(parent) > 50;
     }
 }

